ended yesterday, while the other ended today, then matching the events up to today with the events up to yesterday would be intrinsically impossible. For the events up to today are more numerous, so how could one series match the other? Since such matching is impossible, it may entail an impossible consequence.

A further reply is:

We concede that they are finite at their finite end. But why do you say that, if both are finite at one end, they must also be finite at the end